Of recent years, however, particularly in America, successful attempts have been made to tan the skins of certain fish, notably the shark. The skins are treated with alkali to remove fat and oil, the alkali is then neutralized with acid, after which the skins are washed and tanned. The leather is said to be soft and pliable, and well adapted for many uses. Shark skins are also tanned hard, and used to print a grain on imitation pigskin. Shark fishing was commenced off the American coast in October, 1918. The fish are hunted from fast, powerful motor boats, with specially constructed nets. A small shark 5 ft. long will yield a hide 10 sq. ft. in area. Shark skin is naturally very tough and durable, and in its untanned condition is used by jewellers as a natural emery paper for grinding and polishing metal surfaces. It is also used as an abrasive in working hard woods and ivory. A method has been devised by which a shark skin can be split into three. The first split, after tanning, is strong and thick, and suitable for high grade, heavy shoes. The second furnishes leather suitable for second grade foot wear, and the third resembles suede and is used in making fancy articles. In addition to the shark’s skin, the fins, blood, teeth, flesh, and oil of the fish are also utilized commercially and yield a satisfactory profit. INDEX Ambergris, 106 Anadromous fish, 38 Angler (devil) fish, 18, 32 Beam trawl, 46, 77, 86 Berried lobsters, etc., 35 Bivalve, 94 Black (southern right) whale, 100, 102 Bloater, 60, 66 Blue whale, 104 Brill, 24, 31, 78 Brine pickling, 5, 110 Cachalot (sperm) whale, 100, 104 Canning of fish, 92, 93, 108, 120 Capelan, 70, 100 Cast net, 52 Cat-fish, 16 Clams, 73 Cockle, 25, 27, 53, 74, 90, 93 Cod, 2, 19, 21, 22, 30, 31, 32, 34, 37, 43, 48, 69, 78, 86, 89 —— fishing, 69-76 —— liver oil, 69, 76 Cold storage, 108 Cooking of fish, 122 Copepoda, 27, 30, 36, 90 Crab, 25, 35, 52, 90 Cran, 58, 64 Crustacea, 25, 27, 30, 31, 36, 90, 102 Cutter, 77 Demersal fish, 19, 21, 31, 89 Diatom, 28, 90, 96 Distribution of fishes, 18-27 Dog-fish, 31, 32, 34, 35, 116 —— whelk, 94, 96 Dolphin, 24 Dory fishing, 70 Drifter, 10, 50, 56 Drifting, 50, 56-8, 88 Drift net, 50, 56, 77 Drying of fish, 75, 108 Eel, 16, 38, 44 Eggs of fishes, 27, 28, 32, 34, 35, 69, 90 Fin whale, 104 Fish fertilizer, 4, 62, 76, 130 —— glue, 4, 76, 128 —— hatching, 3, 4, 92 —— leather, 4, 132 —— meal, 4 —— oil, 4, 76, 124-8 Fishery salt, 112-114 Fishing grounds, 10, 30, 69, 80-81, 83 —— traps, 42 —— weirs, 42 Fixed engines, 43 Flake drying, 75 Flounder, 16, 19, 22, 32, 39 Food of fishes, 25, 27, 30, 31, 69, 94 —— value of fish, 37, 54, 115 Gills, 16, 24, 25, 31, 94, 95 Grampus whale, 24, 104 Grayfish, 116 Greenland (Arctic right) whale, 99, 102 Gutting fish, 72, 113